SpringJPA：添加具有當前用戶ID的物體作為外鍵

我正在使用 Thymeleaf HTML 注冊表單和簡單的保存/更新方法將“dish”物件保存/更新到 mySQL 資料庫。Restaurant Id 是“dish”的外鍵，但使用以下方法將其保存為“null”，

我想讓當前登錄的餐廳老板的餐廳 ID 在他們添加一道菜時自動保存。

有沒有簡單的方法來做到這一點？我在 Youtube 上找到的最接近的教程涉及在 Postman 中使用 JSON 請求，過去我在將其調整為 HTML 注冊表單時遇到了問題。

我對這一切都很陌生，因此非常感謝任何幫助！

見菜類：

package com.bron.demoJPA.appuser;
    
@Entity
@Data
@AllArgsConstructor
@NoArgsConstructor
@Builder
@ToString(exclude = "reqlist")
public class Dish {

    @Id
    @SequenceGenerator(name = "dish_sequence", sequenceName = "dish_sequence", allocationSize = 1)

    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "dish_sequence")
    @Column(name = "dish_Id")
    private Long dishId;

    @Column(name = "dish_name")
    private String dname;

    @Column(name = "dish_description")
    private String description;

    @Column(name = "dish_price")
    private double price;

    @ManyToOne(cascade = CascadeType.ALL)
    @JoinColumn(name = "Rest_ID", referencedColumnName = "Rest_ID")
    private AppUser app;

    @ManyToMany(cascade = CascadeType.ALL)

    @JoinTable(name = "dish_requirment_mapping", joinColumns = @JoinColumn(name = "dish_Id", referencedColumnName = "dish_Id"), inverseJoinColumns = @JoinColumn(name = "Require_ID", referencedColumnName = "Require_ID"))
    private List<Requirments> reqlist;

    public void addRequirments(Requirments req) {
        if (reqlist == null)
            reqlist = new ArrayList<>();
        reqlist.add(req);

    }
}

見 AppUser(restaurant owner) 類

    @Column(name = "Rest_Password")
    private String password;

    @Column(name = "Rest_Email_Address")
    private String email;

    @Enumerated(EnumType.STRING)
    private AppUserRole appUserRole;
    private Boolean locked = false;
    // don't enable user until email verification
    private Boolean enabled = false;

    public AppUser(String restname, String email, String pass, AppUserRole app) {
        this.restaurantName = restname;
        this.email = email;
        this.password = pass;
        this.appUserRole = app;
    }

    public Collection<? extends GrantedAuthority> getAuthorities() {
        SimpleGrantedAuthority authority = new SimpleGrantedAuthority(appUserRole.name());
        return Collections.singletonList(authority);
    }

    @Override
    public String getUsername() {
        return email;
    }

    @Override
    public String getPassword() {
        return password;
    }

    @Override
    public boolean isAccountNonExpired() {
        return true;
    }

    @Override
    public boolean isAccountNonLocked() {
        return !locked;
    }

    @Override
    public boolean isCredentialsNonExpired() {
        return true;
    }

    @Override
    public boolean isEnabled() {
        return enabled;
    }

    @OneToOne(cascade = CascadeType.ALL, fetch = FetchType.LAZY, optional = true)

    @JoinColumn(name = "openingHourID", referencedColumnName = "OpeningHour_ID")
    private OpeningHour opening;
}

見控制器類：

package com.bron.demoJPA.conroller;
@Controller
public class DishController {
//display list of employees
    @Autowired
    private DishService dishService;

    @GetMapping("/dish")
    public String viewHomePage(Model model) {
        model.addAttribute("listDish", dishService.getAllDish());
        return "index";
    }

    @GetMapping("/showNewDishForm")
    public String showNewDishForm(Model model) {
        // Create model attribute to bind form data
        Dish dish = new Dish();
        model.addAttribute("dish", dish);
        return "new_dish";
    }

    @PostMapping("/saveDish")
    public String saveDish(@ModelAttribute("dish") Dish dish) {
        // save dish to database
        dishService.saveDish(dish);
        return "redirect:/dish";
    }



@GetMapping("/showFormForUpdate/{dishId}")
    public String showFormForUpdate(@PathVariable(value = "dishId") long dishId, Model model) {
        // get dish from service
        Dish dish = dishService.getDishByDishId(dishId);

        // set dish as model to pre-populate the form data
        model.addAttribute("dish", dish);
        return "update_dish";

    }

}

查看服務實作

package com.bron.demoJPA.service;

import java.util.List;
import java.util.Optional;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.bron.demoJPA.appuser.Dish;
import com.bron.demoJPA.repository.DishRepository;

@Service
public class DishServiceImpl implements DishService {

    @Autowired
    private DishRepository dishRepository;

    @Override
    public List<Dish> getAllDish() {
        return dishRepository.findAll();
    }

    @Override
    public void saveDish(Dish dish) {
        this.dishRepository.save(dish);
    }

    @Override
    public Dish getDishByDishId(long dishId) {
        Optional<Dish> optional = dishRepository.findById(dishId);
        Dish dish = null;
        if (optional.isPresent()) {
            dish = optional.get();
        } else {
            throw new RuntimeException("Dish not found for: "   dishId);
        }
        return dish;
    }
}

見服務類

public interface DishService {

    List<Dish> getAllDish();

    void saveDish(Dish dish);

    Dish getDishByDishId(long dishId);

}

uj5u.com熱心網友回復：

在嘗試保存之前，您能否確保 Dish 的“app”屬性設定正確？

如果它是 null 或者它是 AppUser 類的一個全新實體，那么在嘗試匹配和持久化時它最終會為 null 是有道理的。

你好！

標籤：弹簧 mvc 弹簧数据-jpa 节省 百里香叶 crud-repository

上一篇：Python：將置信區間的輸出轉換為excel

下一篇：webpack-scss無法決議背景影像url